Official locator strategies for the webdriver

Yes, you saw it right.

As per the current WebDriver – W3C Candidate Recommendation the Locator Strategies enlisted are as follows:

• “css selector”: CSS selector
• “link text”: Link text selector
• “partial link text”: Partial link text selector
• “tag name”: Tag name
• “xpath”: XPath selector

Snapshot:

However, the JsonWireProtocol was once used to support the Locator Strategies enlisted below, but currently the documentation clearly states its Status as obsolete:

• class name: Returns an element whose class name contains the search value; compound class names are not permitted.
• css selector: Returns an element matching a CSS selector.
• id: Returns an element whose ID attribute matches the search value.
• name: Returns an element whose NAME attribute matches the search value.
• link text: Returns an anchor element whose visible text matches the search value.
• partial link text: Returns an anchor element whose visible text partially matches the search value.
• tag name: Returns an element whose tag name matches the search value.
• xpath: Returns an element matching an XPath expression. The provided XPath expression must be applied to the server “as is”; if the expression is not relative to the element root, the server should not modify it. Consequently, an XPath query may return elements not contained in the root element’s subtree.

Snapshot:

The change was propagated through the respective client-specific bindings. For the Selenium-Java clients here is the client code where we have the switch case working for the users:

        switch (using) {
          case "class name":
            toReturn.put("using", "css selector");
            toReturn.put("value", "." + cssEscape(value));
            break;

          case "id":
            toReturn.put("using", "css selector");
            toReturn.put("value", "#" + cssEscape(value));
            break;

          case "link text":
            // Do nothing
            break;

          case "name":
            toReturn.put("using", "css selector");
            toReturn.put("value", "*[name="" + value + ""]");
            break;

          case "partial link text":
            // Do nothing
            break;

          case "tag name":
            toReturn.put("using", "css selector");
            toReturn.put("value", cssEscape(value));
            break;

          case "xpath":
            // Do nothing
            break;
        }
        return toReturn;

Snapshot:

Now, your question must be why this change in the W3C specification and in the clients. As per #1042 the answer from the WebDriver Contributors was pretty straight as:

This keeps the specification simple as these can be implemented using the CSS selector, which maps down to querySelector/querySelectorAll.